Shoe tensioning linkage for meat skinner

ABSTRACT

A skinning machine includes a frame, a linkage assembly mounted to the frame, and a skinning assembly mounted to the linkage assembly via lift arms. The linkage assembly raises and lowers the skinning assembly via the lift arms from an open to a closed position, wherein the linkage assembly is located on one side of the skinning assembly. A spring cartridge is operatively associated with the lift arms via an intermediate link to equally apply bias force from the spring cartridge to the independently rotatable lift arms. The linkage assembly includes a cam slot provided through a cam arm to slidably receive a pin therein. The cam slot is shaped to lock the pin when the linkage assembly is in the closed position. A cam block is mounted to the frame and includes a cam notch adapted to slidably secure the end of the pin in a locked open position.

BACKGROUND OF THE INVENTION

This invention is directed toward skinning machines for removing skinand fat from meat parts, and more particularly toward a skinning machinethat has a linkage assembly adapted to raise and lower a skinningassembly on the skinning machine.

In the meat processing industry, it is necessary and desirable to removethe skin and/or fat from a meat part, before separating the muscles forprocessing. To date, this is often done manually, using knives. Not onlydoes this manual method require substantial labor, but it also is timeconsuming and creates safety hazards with the potential for lacerationsand cumulative trauma injuries. Alternatively, automated systems havebeen used to remove the skin and/or fat, but these conventionalautomated systems have an abundance of parts with a great number of wearpoints, and also have insufficient means for properly balancing theforce on both sides of the skinning assembly.

Specifically, typical automated systems are used in a variety ofapplications, each with unique requirements of the machine setup. Inseveral of these applications, it is necessary for a shoe of theskinning assembly to rigidly maintain position relative to a toothroll.In others, it is necessary for the shoe to “float” relative to thetoothroll, so it can respond to variations in product thickness. In someof these automated systems, mounting of the shoe is accommodated in avariety of ways. Often, the shoe mounting mechanism is the mostsophisticated part of the machine, and it has a fundamental impact onthe operating performance of the skinner. In general, the skinningassembly is positioned either rigidly or non-rigidly to “float” oneither end. Generally, it is desirable to allow the shoe to float insuch a way that the two sides of the shoe can move independently. Thus,one side of the blade on the skinning assembly may take a deeper cut inthe product than the opposite side of the blade. Additionally, theskinning assembly may be cleaned by elevating the skinning assembly intoa cleaning position. In the cleaning position, the skinning assembly maybe located far enough away from the toothroll to facilitate wash down ofthe toothroll and all sides of the skinning assembly.

These conventional skinning machines work well for certain applications,but suffer from certain deficiencies. Specifically, a large number ofparts are required for providing “float” capabilities to the skinningassembly, as well as providing a mechanism for elevating the skinningassembly. With this large number of parts, there are a great deal ofpoints prone to wear in the conventional skinning machines.Additionally, in skinning machines where the skinning assembly “floats”,there is a lack of any mechanism for balancing the force applied betweenthe two sides of the skinning assembly.

Therefore, a primary objective of this invention is to provide anapparatus for self-balancing between the two sides of the skinningassembly.

Another objective of this invention is to provide a skinning machinewith fewer parts that are more economical to manufacture.

A further objective of this invention is to provide an apparatus forlifting the skinning assembly with an asymmetric design primarilylocated on one side of the skinning assembly.

These and other objectives will be apparent to those skilled in the artbased on the following disclosure.

SUMMARY OF THE INVENTION

A skinning machine includes a frame, a linkage assembly mounted to theframe, and a skinning assembly mounted to the linkage assembly via liftarms. The linkage assembly is adapted to raise and lower the skinningassembly via the lift arms from an open position for cleaning to aclosed position for skinning, wherein the linkage assembly is located onone side of the skinning assembly. A spring cartridge is operativelyassociated with the lift arms via an intermediate link, wherein theintermediate link is adapted to equally apply bias force from the springcartridge to the independently rotatable lift arms.

A release lever is rotatably mounted on the frame so that a user canmove the linkage assembly from a closed position to an open position.The linkage assembly includes a cam arm attached to the release lever torotate therewith. A cam slot is provided through the cam arm to slidablyreceive a pin therein, wherein the cam slot is shaped to lock the pinwhen the linkage assembly is in the closed position. A clevis attachedto the spring cartridge secures the pin within the cam slot so that anend of the pin extends from the edge of the clevis. A cam block mountedto the frame includes a cam notch adapted to slidably receive the end ofthe pin extending from the clevis to lock the assembly in a raised oropen position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a skinning machine;

FIG. 2 is a cross sectional view of the toothroll and skinning assemblytaken along line 2—2 of FIG. 1;

FIG. 3 is a perspective view of a linkage assembly and skinningassembly;

FIG. 4 is a side elevation view of the linkage assembly in the closedposition;

FIG. 5 is a side elevation view of the linkage assembly in the openposition; and

FIG. 6 is a partial cross sectional view of an intermediate link betweenouter and inner lever arms.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, a skinning machine 10 has a frame 12 with askinning assembly 14 and a toothroll 16 operatively associated with theframe 12. The toothroll 16 is rotatably mounted to the frame 12. Thetoothroll 16 is driven by a drive mechanism (not shown). The drivemechanism includes but is not limited to, any conventional drive deviceoperatively connected to a power source (not shown).

The skinning assembly 14 is positioned in spaced relation to thetoothroll 16. The skinning assembly 14 includes a shoe 18 with a bladeclamp 22 attached thereto for receiving and holding a skinning blade 20.The skinning blade 20 is positioned between the shoe 18 and the clamp 22such that blade 20 is adjacent the radial surface of the toothroll 16.The toothroll 16 assists in directing a layer of skin and/or fat of ameat part (not shown) between the shoe 18 and the toothroll 16. Thetoothroll 16, shoe 18, and skinning blade 20 remove the skin and/or fatfrom the meat part and provide a pulling force to pull the layer of skinand/or fat toward the skinning assembly 14.

Referring to FIGS. 3–5, a linkage assembly 26 is mounted to the frame12. The linkage assembly 26 is adapted to raise and lower the skinningassembly 14 via first and second lift arms 28, 30 from an open positionfor cleaning (see FIG. 5) to a closed position for skinning (see FIG.4). As shown, the linkage assembly 26 is located on one side of theskinning assembly 14.

The linkage assembly 26 includes a release lever 32 rotatably mounted tothe frame 12 so that the linkage assembly 26 moves the skinning assemblyfrom a closed (FIG. 4) to an open position (FIG. 5). A cam arm 34 isattached to the release lever 32 to rotate therewith and has a stop 35that extends outwardly from the cam arm 34 and a cam slot 36 adjacentthe stop 35. The cam arm 34 may comprise a single cam arm operativelyassociated with both the lift arms 28, 30 to raise and lower theskinning assembly 14. The cam slot slidably receives a pin 38 thereinand has a concave arcuate side that assists in forcing the pin 38 to alocked position.

The pin 38 is mounted to and extends between a clevis 40 such that thecam arm 34 is retained within the clevis 40. The clevis 40 has a fingerportion 42 that extends outwardly and engages the stop 35 so that theclevis 40 does not slip out of position when the linkage assembly 14 isin the closed position (see FIG. 4).

A cam block 46 is secured to the frame 12 and includes a cam notch 48located therein. The cam notch 48 includes a surface adapted to slidablyreceive an end of the pin 38 extending from the clevis 40. The cam notch48 is shaped to lock the pin 38 when the linkage assembly 26 is in theopen position (see FIG. 5). Specifically, the cam slot 36 works inconjunction with pin 38 and cam notch 48 to draw pin 38 into the lockedposition when lever 32 is moved to the open position.

A spring cartridge 50 is connected to and extends longitudinally fromthe clevis 40. The spring cartridge 50 provides a positive bias force onthe clevis 40. This positive bias force on the clevis 40 assists inlocking the pin 38 in the cam slot 36 when the linkage assembly 26 is inthe closed position (see FIG. 4). As shown, the spring cartridge 50 ofthe linkage assembly 26 may comprise a single spring cartridgeoperatively associated with both the lift arms 28, 30.

Referring to FIGS. 3 and 6, first and second lever arms 52, 54 areattached to the spring cartridge 50 via an intermediate link 56. Theintermediate link 56 is connected to first and second lever arms 52, 54via spherical bearings or the like such that first and second lever arms52, 54 may rotate with respect to one another. Additionally oralternatively, the intermediate link 56 also applies a bias force toboth the first and second lever arms 52, 54.

A Cylinder 58 is operatively connected to lift arms 28 and 30 and leverarms 52 and 54. The cylinder 58 has a first section 60 and a secondsection 62. The first section 60 is connected to lift arm 28 at one endand has a stem 64 that extends through an aperture in lift arm 30 and isconnected to lever arm 52. The second section 62 has a bore 66 thatextends therethrough and receives the stem portion 64 of the firstsection 60. The second section 62 is connected to lift arm 30 and leverarm 54.

In operation, as a meat part is pulled toward the skinning assembly 14by the toothroll 16 the skinning assembly will float based on variationsin the part's thickness. The end of the skinning assembly 14 connectedto lift arm 28 will float independently of the opposite end connected tolift arm 30. For example, as a thicker portion of the meat part forcesarm 28 upward, the first section 60 of cylinder 58 will rotate inrelation to the second section 62 forcing lever arm 52 downward. Thedownward movement of lever arm 52 is restricted by intermediate link 56.Likewise, if a thicker portion of the meat part forces lift arm 30upward, the second section 62 of the cylinder 58 rotates in relation tothe first section 60 such that lever arm 54 is moved downwardly. Thedownward movement of lever arm 54 is restricted by intermediate link 56.

To open the skinning assembly for cleaning or repair, the lever 32 ismoved downwardly. When the lever 32 moves downwardly, cam arm 34 movestoward cam block 46 causing pin 38 to bottom out in cam slot 36. Whenthe pin 38 bottoms out in cam slot 36 the clevis 40 is drawn toward thecam block 46. As the clevis 40 is drawn toward the cam block 46 thespring cartridge 50 and lever arms 52 and 54 are also drawn toward thecam block 46 such that lift arms 28 and 30 rotate about cylinder 58 tolift the skinning assembly 14 to a raised or open position.

As cam arm 34 moves toward cam block 46, pin 38 engages and is receivedwithin cam notch 48. Cam notch 48 preferably has an arcuate shape with aridge and a lower portion where the pin rides over the ridge and fallsinto the lower portion which locks the skinning assembly 14 in a raisedor open position. In the locked position the pin 38 will not lift out ofnotch 48 when the skinning assembly 14 is moved.

To lower the skinning assembly 14 the lever 32 is raised. When the lever32 is raised, pin 38 slides within notch 48 and slot 36 to release thepin 38 from the cam block 46. This allows the skinning assembly 14 toreturn to the closed or skinning position. The fingers 40 ensure that ascam arm 34 rotates downward, pin 38 slides to the correct position incam slot 36.

With reference to FIGS. 1 and 5, meat parts processed by skinningmachine 10 contact the machine 10 in a zone 68. The skinning assembly 14is located in this food zone 68; however, the linkage assembly 26 islocated primarily within the frame 12 away from the food zone 68. Thislocation of linkage assembly 26 apart from food zone 68, has theadvantage of improving the sanitary nature of the skinning machine 10.Specifically, the moving parts of linkage assembly 26 do not directlycontact processed meat parts, resulting in fewer parts of skinningmachine 10 contacting processed meat parts and therefore reducing theamounts of skinning machine 10 that needs to be sanitized.

Accordingly, a skinning machine having an asymmetrical design located ononly one side of the skinning assembly limiting the number of parts ofthe skinning machine has been described. Likewise, a self-balancingmechanism for balancing the two sides of the skinning assembly via theintermediate link 56 has been described along with a lifting assemblythat locks the skinning machine in an open position for cleaning.

It is therefore seen that the skinning machine will accomplish at leastall of its stated objectives.

1. A skinning machine, comprising: a frame; a linkage assembly mountedto the frame; a skinning assembly mounted to the linkage assembly vialift arms; the linkage assembly connected to the lift arms and adaptedto raise and lower the skinning assembly via the lift arms from an openposition for cleaning to a closed position for skinning, wherein thelinkage assembly is located on one side of the skinning assembly.
 2. Theskinning machine of claim 1, wherein the linkage assembly comprises arelease lever rotatably mounted on the frame so that a user can move thelinkage assembly from a closed to an open position.
 3. A skinningmachine, comprising: a frame; a linkage assembly mounted to the frame; askinning assembly mounted to the linkage assembly via lift arms; and thelinkage assembly adapated to raise and lower the skinning assembly viathe lift arms from an open position for cleaning to a closed positionfor skinning, wherein the linkage assembly is located on one side of theskinning assembly; wherein the linkage assembly comprises a releaselever rotatably mounted on the frame so that a user can move the linkageassembly from a closed to an open position; wherein the linkage assemblycomprises a cam arm attached to the release lever to rotate therewith, acam slot is provided through the cam arm to slidably receive a pintherein, the cam slot is shaped to lock the pin when the linkageassembly is in the closed position.
 4. The skinning machine of claim 3wherein the linkage assembly comprises a single cam arm operativelyassociated with both the lift arms.
 5. The skinning machine of claim 3,wherein the linkage assembly comprises a clevis adapted to secure thepin within the cam slot, a finger surface on the clevis adapted toslidably engage a stop knob extending from the cam arm so that theclevis does not slip out of position when the linkage assembly is in theclosed position.
 6. The skinning machine of claim 3, wherein the linkageassembly comprises a clevis adapted to secure the pin within the camslot so that an end of the pin extends beyond the edge of the clevis, acam block mounted to the frame includes a cam notch adapted to slidablysecure the end of the pin extending from the clevis in a locked openposition.
 7. The skinning machine of claim 3, wherein the linkageassembly comprises a clevis adapted to secure the pin within the camslot, a spring cartridge is connected to the clevis and adapted toprovide a positive bias force on the clevis with respect to the camslot.
 8. The skinning machine of claim 3 wherein the linkage assemblycomprises a single spring cartridge operatively associated with both thelift arms.
 9. The skinning machine of claim 3, wherein the linkageassembly comprises outer and inner lever arms attached to the springcartridge via an intermediate link, wherein the intermediate linkconnects the lower ends of the outer and inner lever arms together sothat the outer and inner lever arms may rotate with respect to oneanother.
 10. The skinning machine of claim 9, wherein the lift armsinclude an outer and an inner lift arm, and wherein the outer lever armand outer lift arm are secured to rotate together, the inner lever armand inner lift arm are secured to rotate together, and wherein the outerlever arm and outer lift arm pair rotate with respect to the inner leverarm and inner lift arm pair.
 11. The skinning machine of claim 9,wherein the intermediate link is adapted to equally apply bias forcefrom and to both the outer and inner lever arms.
 12. A skinning machine,comprising: a frame; a linkage assembly mounted to the frame; a skinningassembly mounted to the linkage assembly via lift arms, wherein the liftarms rotate independently from one another; the linkage assembly adaptedto raise and lower the skinning assembly via the lift arms from an openposition for cleaning to a closed position for skinning, wherein thelinkage assembly comprises a spring cartridge operatively associatedwith the lift arms via an intermediate link, wherein the intermediatelink is adapted to equally apply bias force from the spring cartridge tothe independently rotatable lift arms.